feat(esm): convert to esm (#2569)

for #2543

BREAKING CHANGE: semantic-release is now ESM-only. since it is used through its own executable, the impact on consuming projects should be minimal

BREAKING CHANGE: references to plugin files in configs need to include the file extension because of executing in an ESM context

test/helpers/gitbox.js

@@ -1,7 +1,7 @@
-const Docker = require('dockerode');
-const getStream = require('get-stream');
-const pRetry = require('p-retry');
-const {initBareRepo, gitShallowClone} = require('./git-utils');
+import Docker from 'dockerode';
+import getStream from 'get-stream';
+import pRetry from 'p-retry';
+import {gitShallowClone, initBareRepo} from './git-utils.js';
 
 const IMAGE = 'semanticrelease/docker-gitbox:latest';
 const SERVER_PORT = 80;
@@ -12,12 +12,12 @@ const GIT_PASSWORD = 'suchsecure';
 const docker = new Docker();
 let container;
 
-const gitCredential = `${GIT_USERNAME}:${GIT_PASSWORD}`;
+export const gitCredential = `${GIT_USERNAME}:${GIT_PASSWORD}`;
 
 /**
  * Download the `gitbox` Docker image, create a new container and start it.
  */
-async function start() {
+export async function start() {
   await getStream(await docker.pull(IMAGE));
 
   container = await docker.createContainer({
@@ -38,7 +38,7 @@ async function start() {
 /**
  * Stop and remote the `mockserver` Docker container.
  */
-async function stop() {
+export async function stop() {
   await container.stop();
   await container.remove();
 }
@@ -51,7 +51,7 @@ async function stop() {
  * @param {String} [description=`Repository ${name}`] The repository description.
  * @return {Object} The `repositoryUrl` (URL without auth) and `authUrl` (URL with auth).
  */
-async function createRepo(name, branch = 'master', description = `Repository ${name}`) {
+export async function createRepo(name, branch = 'master', description = `Repository ${name}`) {
   const exec = await container.exec({
     Cmd: ['repo-admin', '-n', name, '-d', description],
     AttachStdout: true,
@@ -68,5 +68,3 @@ async function createRepo(name, branch = 'master', description = `Repository ${n
 
   return {cwd, repositoryUrl, authUrl};
 }
-
-module.exports = {start, stop, gitCredential, createRepo};